Jump to content
Nugget Shooter Forums


old gold miner

Recommended Posts

Why small scale suction dredges are a critical necessity to profitably mine placer gold deposits that still exist today.

With only extremely rare exception, every nook, cranny, and exposed placer gold bearing gravel deposit on dry land in gold mining districts has been worked by one means or another since the days of the great 1849 California gold rush era. Simply because most shallow surface placer gold deposits could be worked with nothing more than hand labor, without extensive investment in equipment.

Below are a few small examples of dry bench workings in gold bearing drainages. That old timers laboriously mined by simply moving cobbles aside, to get to bedrock where placer gold was concentrated. Once an area was stripped to bedrock, they simply swept up the fines, to hand pan, or use a rocker box to concentrate the gold by removing other heavy materials, such as black sands.







Once the dry bench gravels were worked out, in some area’s that were rich in placer gold. If there was a sharp narrow horse shoe bend in the streambed. Miners would sometimes drive a tunnel through the bend. Then, divert the stream, or small river through the tunnel. To expose the former streambed, so they could hand mine the placer gold there. Below are two example where the water diversion technique was used..



Any dry land auriferous gravels that remain today are usually covered with considerable depths of barren overburden, and are very low in placer gold content. To work those remaining dry land placer gold deposits often requires earth moving equipment (bulldozers, drag lines, back hoe excavators, front end loaders, dump trucks, etc), as well as large scale wash plants, in order to recover small amounts of gold from high volume gravel deposits.

To placer mine on that scale often takes a million dollar investment, years of permitting, and significant reclamation bonds. All in all, this type placer mining is usually far beyond the average mans financial ability, to even attempt. The end result being, the only stream or river placer gold deposits of any profitable consequence that remain today. Are in streams or rivers, old time miners could not divert, or work by other means, such as mammoth sized bucket line dredges in areas where extensive gravel deposits were amenable to bucket line dredge mining.



SB 670 does not prohibit the use of hand mining (non-motorized) placer mining. The reality of that is, with ultra-rare exception, there are no profitable small scale stream type placer gold deposits that can be mined profitably, with hand mining methods.

As an example, if one were to discover a wet gravel bar, that contained worthwhile placer gold. To attempt to mine it by hand, is both impractical, and unprofitable.

The ''standard'' round gold pan is 16'' wide at the top, 10'' wide at the bottom, and 2.5'' deep. When full, and level with the top, it would hold about 336 cubic inches, or 0.0072 cubic yard. In theory, this means that 140 pans equal a yard of material. In reality, packed gravels ''swell'' when removed from the ground. A swell of 20 to 25 percent is average.

It can therefore take from 150 to 200 pans to process a yard of material. The figure used most often is 180 pans per yard. Assuming about ten pans per hour, a good panner should be able to pan about a half-yard a day. A very proficient panner working easy small diameter gravel may be able to pan up to a yard a day. This would be grueling day of work, to possibly recover $20 or $30 worth of gold. Alternatively, if the same small diameter gravel was worked with a suction dredge, the operator could recover 10X that amount of gold. With a few hours of relatively easy work.

Link to comment
Share on other sites

Join the conversation

You can post now and register later. If you have an account, sign in now to post with your account.

Reply to this topic...

×   Pasted as rich text.   Paste as plain text instead

  Only 75 emoji are allowed.

×   Your link has been automatically embedded.   Display as a link instead

×   Your previous content has been restored.   Clear editor

×   You cannot paste images directly. Upload or insert images from URL.

  • Recently Browsing   0 members

    • No registered users viewing this page.
  • Create New...